The purpose of this project is to investigate the mechanisms of sperm maturation in the mammalian epididymis and vas deferens. Three specific projects will be studied. 1. Synthesis and secretion of glycoproteins and proteins along the epididymis using biochemical and morphological techniques. 2. An investigation of the functions of the vas deferens. 3. Physiology and morphology of transepithelial water and electrolyte movements in ductuli efferentes and initial segment of the epididymis.